Improvement in air-engines



2gb s--h A. K. RIDER; t s 9? y Improvement in Air Engines. N0, 20325,Patented Oct. 24,1871.

a2 d a2 A All Improvement in Air Engines.

No. 120,325. t Patented-001.1241871.

UNITED STATES PATENT OFFICE.

ALEXANDER K. RIDER, OF NEW YORK, N. Y., ASSIGNOR TO HIMSELF AND O. H.DELAMATER, OF SAME PLAGE.

IMPROVEMENT IN AIR-ENGINES.

Specification forming part of Letters Patent No. 120,325, dated October24, 1871.

To all 'whom t may concern:

Be it known that I, ALEXANDER K. RIDER, of New York city, in the Stateof New York, have invented certain new and useful Improvements inHot-Air Engines, of which the following is a specication My inventionrelates to provisions for making the cylinder serve as a pump by the aidof the same piston which yields the power; a positive motion of thevalve which admits the cold air; a non-conducting lining within thecylinder; a non-conducting lining for the air-pipes and other partsprovisions for heating and reheating the air in the working cylinderafter it has been introduced therein provisions for introducing the airinto the top of the furnace and taking it out again through the sameaperture when the heat is too great; means for arresting the conductionof heat from the hot to the cool end of the cylinder; a peculiarconstruction and arrangement of the door and means for securing it; anarrangement by which a working beam is employed, mounted on movablelinks with a parallel motion; and a lining of the entire furnace withfirebrick, eXcept a portion of the top, which latter comes under thedomed bottom of the working cylinder.

The engine is adapted to stand upright in a small space, and is intendedto work rapidly and to serve as a quick-acting and highly-efficientengine for all general purposes-small manufactures, pumping, &c.

The following is a description of what I consider the best means ofcarrying out the invention.

The accompanying drawing forms a part of this specification.

Figure l is a central vertical section through the entire engine, withits furnace and connections forming parts ofthe same. Fig. 2 is asection through the induction-valve, showin g, also, one of the leverswhich are attached. Fig. 3 is a View of the controlling-valve, which isoperated by a shaft passing through the casing adjacent. It is hereshown as detached and turned onefourth around. Fig. 4 is a horizontalsection through the door and casing. Fig. 5 is a front view of the door,with the bolt, hinges, and fastening.

Similar letters of reference indicate like parts in all the figures.

The cylinder forms a portion of the frame-work of the machine, it andits adj uncts being provided with a broad spreading base. Suitablebrackets and pipes may, if preferable, be cast in one with the adjacentmain castings. These parts, taken together, form the fixed frame-work ofthe machine. I will designate these parts by the single letter A, whennecessary, and the several details by A1 A2, &c.

A1 is the nicely-finished main cylinder. It is provided at its base withbroad flanges al, which are thicker near their periphery than at theirinner edges, and they match to nearly-corresponding anges on the partbelow. The part below is marked A2, and the iiange thereon is marked a2.The flanges, when properly faced and applied together, make a tightunion, either by the direct contact of the metal or by the interpositionof a suitable cement; but such contact and union is only at and near theouter edge. The main breadth of the dan ges are held a little distanceapart. There is a lip, a3, on the upper face of the flange a2, whichmatches against a shoulder on the inner boundary of the bearing surfaceofthe flange A1, and holds the parts stifliy in position laterally.There may be any number of bolts and nuts or other ordinary or suitablemeans for holding the bearing parts of the iianges al a? stron glytogether. The lower casting A2 is necessarily maintained at a hightemperature. The upper casting A1 should be cooler. It follows thatthere is a constant tendency to conduct the heat upward from the hotcasting A2 to the cooler casting A1. This I do not attempt to altogetherprevent; but my construction retards it by compelling the heat to traveloutward on the iange a2,- thence across and preferably through anonconducting cement into the outer edge of the ilange al; thence inwardon the iiange al; and finally upward into the body of the metal of thecool cylinder A1. The long distance which it is, by this construction,compelled to traverse makes the transmission of the heat veryslow. Thehot cylinder A2 is of a larger internal diameter than the main cylinderA1, and contains a lining, A3, which is of a highly nonconductingcharacter. The material which I prefer, and believe to be peculiarlyadapted for this and the other nonconducting linings, will be describedfurther on.

The non-conducting lining in this position, whatever be its material,serves the important function of maintaining a very high temperatureWithin the lower or hot cylinder while imparting a considerable lowertemperature to the metal A2. This is due partly to the fact that thereis a lining in a separate piece from the metal A2, and partly to thefact that the lining-piece is a highly nonconducting material. If thelining was a conductor equal in quality to cast-iron, it would stillserve to some extent as a shield to arrest the conduction of the heat byreason of its thickness, and more especially of the joint or crackbetween itself and the outer piece. `Every such joint tends to arrestthe conduction of the heat 5 but the non-conductor which I employ is farsuperior to cast-iron for this purpose. The piston is thick, and itslower portion is highly non-conductive. It may not be necessary todescribe the preferable materials. I propose to use nre-brick, irebrickdust, nre-clay or other clay, finely-pulverized ashes, iine ashes, orany compounds of these or other non-conducting materials, within acasing of cast-iron or other suitable material but I give thepreference, for lightness and other reasons, to a thin shell of goodsheet-iron riveted up in the proper form and filled with lightly-packedpulverized charcoal. The bottom is deeply recessed, as shown, andadapted to match to a correspondingly-formed bottom-piece, A4, which iseasily detached and renewable at pleasure. A5 is the shell of thefurnace, which, spread out below, forms a broad substantial base of theengine. The framing for the pillow-block or bearing of the main shaft,which bearing is not represented, maybe cast in 011e with or bolted orotherwise fixed to this casting A5; or it may be fixed to the topcasting A1, or to both these parts, or mounted independently, atpleasure. A6 is the grate, and AI a thick non-conducting lining offire-brick, which covers the whole interior of the furnace, including`the base of the heater A4, eX- cept a small space in line with thecenter of the heater, .as shown. The intensely-heated gases from theinterior of the furnace play up and down through the narrow passage thusprovided and heat the interior of the heater A4; but the firebrickprotect such interior from the main portion ofthe radiant heat of thefuel, and thus promote its durability.

Under ordinary conditions, when the engine is being worked at or nearits full power the air flows down through the pipe B into the bottom ofthe furnace; thence up through the grate and fuel, thence laterally outthrough the passage C into the passage D whence it passes the valve F,which is raised by the action of the engine at the proper time, and isthence discharged tangentially into the narrow annular space around thebase of the heater. The air thus conducted travels actively severaltimes around as the piston rises, and effectually licks off the heat,which would otherwise become excessive, and promotes the efficiency ofthe engine by absorbing the heat thereof' into the air. It may beremarked that the air, however intensely heated in the furnace, isliable to become partially cooled in its passage through and retentionin the passage D and its connections. This active circulation in thebase in direct contact with the heater may be said to reheat the air.

There is a condition in which the machine is liable to work at intervalsin some kinds of work. It may work in this condition a large portion ofthe time where the air is carried in a cold or nearly cold state intothe passage D and thence into the base of the working cylinder. This iswhen the engine is yielding too much power.

There may be a regulator of any ordinary or suitable character, notrepresented, attached to the engine to regulate the speed by anyapproved means. When theV heat is greatly in excess lof that requiredthe governor so operates a valve, F, Fig. l, that the air is no longerdischarged, either in whole or in part, through the grate, but is allsent past the furnace in a cold or nearly cold state. The passagethrough which this is effected isshown in part in Fig. l, marked G. Theair thus delivered circulates inward and outward with each fluctuationin its pressure through the passage C, and thus mingles itself more orless with the hot products of combustion and becomes itself partlyheated.

In the engines previously known all the air is carried under theseconditions directly through the upper portion of the furnace; in suchcase it is all subjected to the iniiuence of the nre and to contact withthe intensesly-he'ated surfaces. It also acts to some extent as astimulant to the lire by blowing upon its upper surface.

My arrangement avoids this, an d the only introduction of the cool airinto the furnace is due to the uctuations in its pressure. When thepressure is the greatest the compression of the air in the furnaceallows a portion of the air in the passages D G to flow inward throughthe passage C and increase the quantity in the furnace. When, a momentlater, the lifting of the valve F and the passage of a portion of thecompressed air into the working-cylinder has lowered the pressure, thenthe expansion of the air in the furnace drives out a correspondingquantity in passage C to mingle in the cold air and be carried over intothe cylinder. y

Inviting attention now to the work at or near the top of the machine, itwill be seen that the piston-rod IL is connected directly to the beam Iwithout the intervention of any links; that the beam is mounted by itscenter on stout links J, which receive and resist the up-and-down forceand allow the effect of the piston to be transmitted through theconnecting-rod K to the crank L in the obvious manner, while the links Jare free to turn and allow the beam to accommodate itself' to the truerectilinear motion of the piston-rod. There are parallel-motion rods Jfixed at one end in the beam and the other end tothe stiff brackets A8,which project upward from fixed work below, the functions and properproportions of which are familiar without detailed description. Thespace in the main cylinder A1 above the piston H serves as the pump. Ateach descent of the piston H the air is received through a liberalannular aperture controlled by a valve, M, which may be a ring of metalcovered with any suitable material to fit tightly and act noiselessly. Ihave in my experim ents found leather to do well in this position, andhave also employed double cut leathers as the packing in my piston H.The ring-valve M is held up to its seat during a portion of therevolution by the pressure of the air below; but it is important to holdthe valve wide open during the early portion of' the up-stroke of thepiston. There are two supporting-rods, m, and one at each side of theengine. These rods are fixed to the ringvalve M and are pivoted upon oneend of the loaded lever N There are two of these levers N, one over eachside of the machine, connected to the two rods m. The loaded end of thelever N is just sumciently weighty to balance or a little more thanbalance the valve M. An arm projects upward from each lever N, to whicharm is pivoted a horizontal rod, O, which is guided so that it stands ina horizontal position, and is capable only of a sliding motion backwardand forward. As the valve M rises and sinks by means of these rods O thevalve is held forcibly open during a portion of the up-stroke of thepiston. On the down-stroke of the piston H the valve M sinks and allowsthe cool air to be inducted freely 5 before the piston has completed itsdownstroke an adjustable piece, P, mounted in a slide, Q, connected withthe working-beam I at a point, q, as shown, is moved downward and standsopposite the end of the slide O on each side of the engine-that is tosay, there are two of these slides Q and two of' the adjustable pieces Pcorresponding to the two slides O. When the piston commences to rise anddrives upward the air below the valve M it tends to move the valveupward and close it; but this movement is prevented by the contact ofthe slides O against the pieces P. During all the early portion of theascending motion of the piston H the air above it is allowed to escapefreely past the valve M 5 but when a certain portion, usually aboutone-third, of the 11p-stroke has been performed, the pieces P have movedup sufficiently to liberate the slides O, and now the levers N areallowed to tilt and the valve M to close. After this change of conditionthe air above the piston becomes compressed by the further ascent of thepiston and is ultimately delivered through the valve It into the passageB, and thence passes where it is made efficient in driving the engine,as before explained. By reason of the adjustability of the pieces P theperiod at which the valve M is allowed to close may be made earlier orlater, at pleasure.

It is important that the aperture of' the door of the furnace beconveniently opened and closed with little labor, and that the closingmay be made very tight. I have provided for this by means ofl a stoutsliding bar, peculiarly mounted, and provided with screws for pressingagainst the door after the bar or bolt is secgred. T is the door,turning on the hinge t. U is a stout bolt provided with a slot, whichembraces the pin t and permits a sufficient end motion to allow it toserve as a bolt. When the door T is to be opened or shut the bolt U isdrawn backward to liberate it from the keeper A9; but when the door isclosed and it is desired to secure it tightly it is necessary simply tomove the stout bar or bolt U bodily so as to engage with the keeper A9,and then to turn the screws V V, which are tapped through the bolt U andact directly against the door T. The inner face of' the door T may belined with a non-conductor.

I have provided a non conducting lining within the pipe D and pipe O aswell as within the hot portiomof the cylinder. All these non-conductinglinings may be made by holding ashes, pulverized, or other goodnon-conductor, in position by a casing of sheet-iron or the like 3 butthis is not the best plan. I have discovered that in this position agood lining can be made with a mixture of about equal weights ofcalcined plaster and ground glass; the glass may be in the condition inwhich it is prepared in the market for the manufacture of fine abrasivesurfaces. The plaster may be the ordinary calcined material. On beingthoroughly mixed in the proportions here design ated and moistened witha proper quantity of' water the plastic material may be made to adhereto the inner surface ofthe main cylinder A2 and to the inner surface of'the pipe D and C. It will harden and form a very tenacious coating,while its non-conducting qualities are remarkable.

I esteem this manufacture of lining an important feature in myinvention. The contour of' the inner faces of the parts of the lining ofall the parts may be formed and preserved by molding with any suitableremovable material.

Although I have shown only one flange, al, and one flange, ai", adaptedto cause the heat to traverse out and back once in its transmission fromthe hot cylinder A2 to the cool cylinder A1, I propose in some instancesto employ a greater number by introducing rings with corresponding broadflanges between these flanges, so as to cause the heat to traverse outand in as many times as may be desired. The quantity of air contained inthe thin spaces provided between the iianges will produce no appreciableeffect in the working of the engine, and the elasticity of the partswill not,I think, be sufficient to induce any appreciable mischief.

I claim as my improvements in air-engines- 1. The mode of operation ofthe valve M to allow the escape of' air during a portion of the strokeand to close and compel the delivery of' the air through the valve Rduring the remainder of the stroke, so as to make the main cylinder A1and main piston H serve as the compressing-pump for delivering a smallervolume of air than the capacity of' the cylinder, as specified.

2. The adjustable pieces P or their equivalents, operated by the engine,and serving' to hold open the induction-valve M during a variableportion of the return stroke, substantially as herein specified.

3. The construction and arrangement of the heater A4 and the adjacentparts, and tangential passage through which the air is delivered, sothat the air shall traverse around -in the space provided f'or thepurposes specified.

4. The passages Gr,D, and C, arranged, as represented, relatively to thevalve F and to the Working parts of an air-engine, so that the cool airshall be only partially introduced into the top of the furnace, asspecified.

5. The broad flanges al a2 bearing at or near their outer edges, asrepresented, to prevent the conduction of the heat between the partsWhile maintaining a rrn union thereof, as speoilied.

6. The tightening means V, mounted on the sliding bolt U, and the Wholearranged to traverse on the hinge-joint t and to secure and liberate thedoor T, substantially in the manner as here in specied. Y

7. The beam I, links J, connecting-rod K, parallel-motion links J1, andbrackets A8, arranged, as represented, relatively to each other and tothe piston-rod h, and to theValve-operatin g means Q q l) N, for thepurposes set forth.

In testimony whereof I have set my name in presence of two subscribingWitnesses.

- A. K. RIDER.

